Research in minimum undeformed chip thickness and size effect in micro end-milling of potassium dihydrogen phosphate crystal

In precision and micro cutting processes, the tool cutting edge radius is generally quite large compared to the undeformed chip thickness, which can cause ploughing/rubbing between the tool and the workpiece and thus affect surface finish, tool wear, and burr formation. This paper investigates the effect of the size effect on top burr formation in two-dimensional vibration-assisted micro end milling (2D VAMEM). This is achieved by studying the effects of the ratio of undeformed chip thickness to the cutting edge radius, and the ratio of the time when the undeformed chip thickness is less than the minimum chip thickness to the total cutting time on top burr formation, using a model that integrates the chip thickness model of the 2D VAMEM and the minimum chip thickness prediction model. The corresponding experiments are carried out to verify the integrated model. It is found that feed per tooth has a significant effect on the height of the top burr, and the use of vibration-assisted cutting in micro end milling can minimize the size effect and improve the cutting performance, thereby reducing the height of the top burr. In addition, selecting suitable vibration parameters can significantly decrease the height of the top burr. The integrated model can be used to optimize the machining parameters to reduce burr size and further study the size effect on cutting force, surface roughness, and tool wear in 2D VAMEM.

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Cutting surface quality analysis in micro ball end-milling of KDP crystal considering size effect and minimum undeformed chip thickness

Precision Engineering ◽

10.1016/j.precisioneng.2017.06.015 ◽

2017 ◽

Vol 50 ◽

pp. 410-420 ◽

Cited By ~ 16

Author(s):

Ni Chen ◽

Mingjun Chen ◽

Chunya Wu ◽

Xudong Pei

Keyword(s):

Size Effect ◽

Surface Quality ◽

End Milling ◽

Chip Thickness ◽

Quality Analysis ◽

Kdp Crystal ◽

Undeformed Chip Thickness ◽

Ball End Milling ◽

Cutting Surface

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Critical Undeformed Chip Thickness and Cutting Pressure in Relation to Ductile Mode Cutting of KDP Crystal

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.443.582 ◽

2010 ◽

Vol 443 ◽

pp. 582-587 ◽

Cited By ~ 2

Author(s):

Hao Feng Chen ◽

Zi Wen Zheng ◽

Yi Fan Dai ◽

Hang Gao ◽

Xiao Ping Li

Keyword(s):

Potassium Dihydrogen Phosphate ◽

Chip Thickness ◽

Groove Depth ◽

Dihydrogen Phosphate ◽

Main Process ◽

Crystalline Orientation ◽

Undeformed Chip Thickness ◽

Process Characteristics ◽

Ductile Mode Cutting ◽

Depth Increase

Microgroove processes are carried out on Potassium Dihydrogen Phosphate (KDP) crystals of different crystalline orientation using diamond tool, the speed of groove is very low in order to avoid the influence of temperature. The main process characteristics are examined including the groove geometry, cutting forces and critical underformed chip thickness at the onset of ductile-to-brittle cutting transition. Additionally, the cutting pressure is calculated from the cutting force and grooving geometry. The experimental results show that as the groove depth increase, the groove geometry clearly revealed that ductile-to-brittle cutting transition occurred, and the transition are well reflected by changing in the cutting pressure. Further, it is shown that the critical undeformed chip thickness varies greatly with the workpiece KDP crystalline orientation.

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Research on the Relationship between Cutting Force and Machined Surface Quality in Micro Ball End-Milling of Potassium Dihydrogen Phosphate Crystal

Micromachines ◽

10.3390/mi9110574 ◽

2018 ◽

Vol 9 (11) ◽

pp. 574

Author(s):

Ni Chen ◽

Chunya Wu ◽

Mingjun Chen ◽

Liang Li ◽

Ning He

Keyword(s):

Cutting Force ◽

Thrust Force ◽

End Milling ◽

Potassium Dihydrogen Phosphate ◽

Spindle Speed ◽

Dihydrogen Phosphate ◽

Dimensional Error ◽

Kdp Crystal ◽

Potassium Dihydrogen ◽

The Relationship

Potassium dihydrogen phosphate (KDP or KH2PO4) crystal is widely used as terminal frequency converters in inertial confinement fusion (ICF). However, KDP crystal is a typical difficult-to-cut optical crystal with the characteristic of soft-brittle. In this work, the relationship between cutting force and processed surface quality in micro ball end-milling of KDP crystal with various depth of cut and spindle speed is studied by carried out the micro-milling experiments. Fast Fourier Transform (FFT) algorithm is used to diagnose the recorded cutting force. The periodic change of cutting force and the cutting force after filtering noises can be got through FFT analysis. Through calculating the correlation coefficients between the static component of thrust force and roughness value Ra of machined grooves, as well as the peak-valley (P-V) value of thrust force and dimensional error of machined grooves, the roughness value Ra and dimensional error of machined grooves would be predicted by monitoring the static component and P-V value of the thrust force, respectively. The relatively large spindle speed helps to reduce the roughness value Ra. The spindle speed with moderate value is recommended to reduce the dimensional error of machined groove because the dimensional error of machined groove will increase when the spindle speed is small enough (causing brittle cutting) or large enough (reducing cutting stability).

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Modeling the Impact of Flow Modulation on Surface Structure during the Growth of Potassium Dihydrogen Phosphate Single Crystals from Solution

International Journal for Multiscale Computational Engineering ◽

10.1615/intjmultcompeng.v6.i6.60 ◽

2008 ◽

Vol 6 (6) ◽

pp. 585-601

Author(s):

Igal Rasin ◽

Simon Brandon ◽

Oleg Weinstein

Keyword(s):

Surface Structure ◽

Single Crystals ◽

Potassium Dihydrogen Phosphate ◽

Dihydrogen Phosphate ◽

Potassium Dihydrogen ◽

Flow Modulation ◽

The Impact

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Optical Absorption Spectra of Vanadyl Ion (Impurities) in Three Host Crystal Compounds

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-1116 ◽

1985 ◽

Vol 40 (11) ◽

pp. 1164-1166

Author(s):

O. P. Agarwal ◽

Prem Chand

Keyword(s):

Optical Absorption ◽

Potassium Dihydrogen Phosphate ◽

Optical Data ◽

Dihydrogen Phosphate ◽

Host Crystal ◽

Optical Absorption Study ◽

Potassium Dihydrogen ◽

Vanadyl Complexes ◽

Vanadyl Ion ◽

Magnesium Ammonium

Results of the optical absorption study of vanadyl ion doped in magnesium ammonium sulphate hexahydrate, rubidium sulphate and potassium dihydrogen phosphate single crystals at RT are reported. The nature of optical bands suggests a C4v symmetry of the Vanadyl complexes in conformity with the EPR results. Powder EPR data and optical data are correlated to obtain the MO coefficients.

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The Strain Rate Sensitivity and Creep Behavior for the Tripler Plane of Potassium Dihydrogen Phosphate Crystal by Nanoindentation

Micromachines ◽

10.3390/mi12040369 ◽

2021 ◽

Vol 12 (4) ◽

pp. 369

Author(s):

Jianhui Mao ◽

Wenjun Liu ◽

Dongfang Li ◽

Chenkai Zhang ◽

Yi Ma

Keyword(s):

Strain Rate ◽

Strain Rate Sensitivity ◽

Creep Deformation ◽

Potassium Dihydrogen Phosphate ◽

Rate Sensitivity ◽

Dislocation Nucleation ◽

Machining Process ◽

Dihydrogen Phosphate ◽

Potassium Dihydrogen ◽

Kdp Crystals

As an excellent multifunctional single crystal, potassium dihydrogen phosphate (KDP) is a well-known, difficult-to-process material for its soft-brittle and deliquescent nature. The surface mechanical properties are critical to the machining process; however, the characteristics of deformation behavior for KDP crystals have not been well studied. In this work, the strain rate effect on hardness was investigated on the mechanically polished tripler plane of a KDP crystal relying on nanoindentation technology. By increasing the strain rate from 0.001 to 0.1 s−1, hardness increased from 1.67 to 2.07 GPa. Hence, the strain rate sensitivity was determined as 0.053, and the activation volume of dislocation nucleation was 169 Å3. Based on the constant load-holding method, creep deformation was studied at various holding depths at room temperature. Under the spherical tip, creep deformation could be greatly enhanced with increasing holding depth, which was mainly due to the enlarged holding strain. Under the self-similar Berkovich indenter, creep strain could be reduced at a deeper location. Such an indentation size effect on creep deformation was firstly reported for KDP crystals. The strain rate sensitivity of the steady-state creep flow was estimated, and the creep mechanism was qualitatively discussed.

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